linux.git/tools/perf/builtin-diff.c, branch v6.12.80

perf report: Display the branch counter histogram

2024-08-14T13:20:40+00:00

Reusing the existing --total-cycles option to display the branch
counters. Add a new PERF_HPP_REPORT__BLOCK_BRANCH_COUNTER to display
the logged branch counter events. They are shown right after all the
cycle-related annotations.

Extend the 'struct block_info' to store and pass the branch counter
related information.

The annotation_br_cntr_entry() is to print the histogram of each branch
counter event. If the number of logged events is less than 4, the exact
number of the abbr name is printed. Otherwise, using '+' to stands for
more than 3 events.

Assume the number of logged events is less than 4.

The annotation_br_cntr_abbr_list() prints the branch counter's
abbreviation list. Press 'B' to display the list in the TUI mode.

  $ perf record -e "{branch-instructions:ppp,branch-misses}:S" -j any,counter
  $ perf report  --total-cycles --stdio

  # To display the perf.data header info, please use --header/--header-only options.
  #
  #
  # Total Lost Samples: 0
  #
  # Samples: 1M of events 'anon group { branch-instructions:ppp, branch-misses }'
  # Event count (approx.): 1610046
  #
  # Branch counter abbr list:
  # branch-instructions:ppp = A
  # branch-misses = B
  # '-' No event occurs
  # '+' Event occurrences may be lost due to branch counter saturated
  #
  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles  Branch Counter [Program Block Range]
  # ...............  ..............  ...........  ..........  ..............  ..................
  #
            57.55%            2.5M        0.00%           3     |A   |-   |                 ...
            25.27%            1.1M        0.00%           2     |AA  |-   |                 ...
            15.61%          667.2K        0.00%           1     |A   |-   |                 ...
             0.16%            6.9K        0.81%         575     |A   |-   |                 ...
             0.16%            6.8K        1.38%         977     |AA  |-   |                 ...
             0.16%            6.8K        0.04%          28     |AA  |B   |                 ...
             0.15%            6.6K        1.33%         946     |A   |-   |                 ...
             0.11%            4.5K        0.06%          46     |AAA+|-   |                 ...
             0.10%            4.4K        0.88%         624     |A   |-   |                 ...
             0.09%            3.7K        0.74%         524     |AAA+|B   |                 ...

With -v applied,

  # Sampled Cycles%  Sampled Cycles  Avg Cycles%  Avg Cycles  Branch Counter [Program Block Range]
  # ...............  ..............  ...........  ..........  ..............  ..................
  #
            57.55%            2.5M        0.00%           3       A=1 ,B=-                  ...
            25.27%            1.1M        0.00%           2       A=2 ,B=-                  ...
            15.61%          667.2K        0.00%           1       A=1 ,B=-                  ...
             0.16%            6.9K        0.81%         575       A=1 ,B=-                  ...
             0.16%            6.8K        1.38%         977       A=2 ,B=-                  ...
             0.16%            6.8K        0.04%          28       A=2 ,B=1                  ...
             0.15%            6.6K        1.33%         946       A=1 ,B=-                  ...
             0.11%            4.5K        0.06%          46       A=3+,B=-                  ...
             0.10%            4.4K        0.88%         624       A=1 ,B=-                  ...
             0.09%            3.7K        0.74%         524       A=3+,B=1                  ...

Reviewed-by: Andi Kleen 
Signed-off-by: Kan Liang 
Acked-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20240813160208.2493643-7-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Save branch counters for each block

2024-08-14T13:20:40+00:00

When annotating a basic block, it's useful to display the occurrences
of other events in the block.

The branch counter feature is only available for newer Intel platforms.

So a dedicated option to display the branch counters is not introduced.

Reuse the existing --total-cycles option, which triggers the annotation
of a basic block and displays the cycle-related annotation.

When the branch counters information is available, the branch counters
are automatically appended after all the cycle-related annotation.

Accounting the branch counters as well when accounting the cycles in
hist__account_cycles().

In 'struct annotated_branch', introduce a br_cntr array to save the
accumulation of each branch counter.

In a sample, all the branch counters for a branch are saved in a u64
space.

Because the saturation of a branch counter is small, e.g., for Intel
Sierra Forest, the saturation is only 3.

Add ANNOTATION__BR_CNTR_SATURATED_FLAG to indicate if a branch counter
once saturated. That can be used to indicate a potential event lost
because of the saturation.

Reviewed-by: Andi Kleen 
Signed-off-by: Kan Liang 
Acked-by: Namhyung Kim 
Cc: Adrian Hunter 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: Stephane Eranian 
Link: https://lore.kernel.org/r/20240813160208.2493643-5-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Use perf_tool__init()

2024-08-12T21:12:26+00:00

Use perf_tool__init() so that more uses of 'struct perf_tool' can be const
and not relying on perf_tool__fill_defaults().

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Anshuman Khandual 
Cc: Athira Rajeev 
Cc: Huacai Chen 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Jonathan Cameron 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Nick Desaulniers 
Cc: Nick Terrell 
Cc: Oliver Upton 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Suzuki Poulouse 
Cc: Will Deacon 
Cc: Yanteng Si 
Cc: Yicong Yang 
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20240812204720.631678-22-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf tool: Constify tool pointers

2024-08-12T21:05:14+00:00

The tool pointer (to a struct largely of function pointers) is passed
around but is unchanged except at initialization. Change parameter and
variable types to be const to lower the possibilities of what could
happen with a tool.

Reviewed-by: Adrian Hunter 
Signed-off-by: Ian Rogers 
Tested-by: Adrian Hunter 
Tested-by: Leo Yan 
Cc: Alexander Shishkin 
Cc: Anshuman Khandual 
Cc: Athira Rajeev 
Cc: Huacai Chen 
Cc: Ilkka Koskinen 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Jonathan Cameron 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Nick Desaulniers 
Cc: Nick Terrell 
Cc: Oliver Upton 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Sun Haiyong 
Cc: Suzuki Poulouse 
Cc: Will Deacon 
Cc: Yanteng Si 
Cc: Yicong Yang 
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20240812204720.631678-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf diff: Replaces some ',' as separator with the more usual ';'

2023-07-20T14:43:45+00:00

When wrapping code, use ';' better than using ',' which is more in line
with the coding habits of most engineers.

Signed-off-by: Lu Hongfei 
Acked-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: opensource.kernel@vivo.com
Link: https://lore.kernel.org/r/20230706094635.1553-1-luhongfei@vivo.com
Signed-off-by: Arnaldo Carvalho de Melo

perf srcline: Optimize comparision against SRCLINE_UNKNOWN

2023-06-12T21:17:00+00:00

This is a string constant that gets returned and then strcmp() around,
we can instead just do a pointer comparision.

That requires a new global variable to comply with these warnings from
some versions of clang and gcc:

  41    68.95 fedora:rawhide                : FAIL clang version 16.0.4 (Fedora 16.0.4-1.fc39)
    result of comparison against a string literal is unspecified (use an explicit string comparison function instead) [-Werror,-Wstring-compare]
            if (start_line != SRCLINE_UNKNOWN &&
                           ^  ~~~~~~~~~~~~~~~  41

Ack comments:

Agreed, the strcmps make me nervous as they won't distinguish heap from
a global meaning we could end up with things like pointers to freed
memory. The comparison with the global is always going to be same imo.

Acked-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Brian Robbins 
Cc: Changbin Du 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Fangrui Song 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: Ivan Babrou 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Liam Howlett 
Cc: Mark Rutland 
Cc: Miguel Ojeda 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Wenyu Liu 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Ye Xingchen 
Cc: Yuan Can 
Link: https://lore.kernel.org/lkml/ZIcoJytUEz4UgQYR@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf srcline: Change free_srcline to zfree_srcline

2023-06-12T18:57:54+00:00

Make use after free more unlikely.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Brian Robbins 
Cc: Changbin Du 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Fangrui Song 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: Ivan Babrou 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Liam Howlett 
Cc: Mark Rutland 
Cc: Miguel Ojeda 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Wenyu Liu 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Ye Xingchen 
Cc: Yuan Can 
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230608232823.4027869-26-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf addr_location: Add init/exit/copy functions

2023-06-12T18:57:53+00:00

struct addr_location holds references to multiple reference counted
objects. Add init/exit functions to make maintenance of those more
consistent with the rest of the code and to try to avoid
leaks. Modification of thread reference counts isn't included in this
change.

Committer notes:

I needed to initialize result to sample->ip to make sure is set to
something, fixing a compile time error, mostly keeping the previous
logic as build_alloc_func_list() already does debugging/error prints
about what went wrong if it takes the 'goto out'.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ali Saidi 
Cc: Andi Kleen 
Cc: Athira Rajeev 
Cc: Brian Robbins 
Cc: Changbin Du 
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: Fangrui Song 
Cc: German Gomez 
Cc: Ingo Molnar 
Cc: Ivan Babrou 
Cc: James Clark 
Cc: Jing Zhang 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: K Prateek Nayak 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Liam Howlett 
Cc: Mark Rutland 
Cc: Miguel Ojeda 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Naveen N. Rao 
Cc: Peter Zijlstra 
Cc: Ravi Bangoria 
Cc: Sean Christopherson 
Cc: Steinar H. Gunderson 
Cc: Suzuki Poulouse 
Cc: Wenyu Liu 
Cc: Will Deacon 
Cc: Yang Jihong 
Cc: Ye Xingchen 
Cc: Yuan Can 
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230608232823.4027869-7-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf util: Move perf_guest/host declarations

2023-04-10T22:22:05+00:00

The definitions are in util.c so move the declarations to match.

Signed-off-by: Ian Rogers 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Athira Rajeev 
Cc: Chengdong Li 
Cc: Denis Nikitin 
Cc: Florian Fischer 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Kan Liang 
Cc: Leo Yan 
Cc: Mark Rutland 
Cc: Martin Liška 
Cc: Mathieu Poirier 
Cc: Mike Leach 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Raul Silvera 
Cc: Ravi Bangoria 
Cc: Rob Herring 
Cc: Sean Christopherson 
Cc: Suzuki Poulouse 
Cc: Will Deacon 
Cc: Xing Zhengjun 
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230410162511.3055900-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo

perf hist: Add 'kvm_info' field in histograms entry

2023-03-15T19:47:20+00:00

__hists__add_entry() creates a temporary entry and compare it with
existed histograms entries, if any existed entry equals to the
temporary entry it skips to allocation to avoid duplication.

The problem for support KVM event in histograms is it doesn't contain
any info to identify KVM event and can be used for comparison entries.

This patch adds 'kvm_info' field in the histograms entry which contains
the KVM event's key, this identifier will be used for comparison
histograms entries in later change.

Signed-off-by: Leo Yan 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: James Clark 
Cc: Jiri Olsa 
Cc: John Garry 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20230315145112.186603-2-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo